# 这是条注释

name = 'yangjh'
print(name)

name = 'yangzh'
print(name)

a, b, c = 1, 2, 3
print(a, b, c)

# 运算符练习

print(3 + 2)
print(8 // 5)
print(8 % 5)
print(2**4)

# 数字类型

print(type(1))
print(type('1'))
print(type(1.5))
print(type(2 + 3j))

print(type(int('1')))
print(type(float('1')))
print(float('1'))

# 序列

# 定义序列，字符串是序列之一。

today = '2021-9-13'
time = '21:00'

print(today[0], today[1], today[-1], today[-2])
print(today[0:2], today[-1:-2])
datetime = today + ' ' + time
print(datetime)
print(3 * time)

print('2' in today)
print('2100' in today)
print('变量today的长度是： ', today.__len__())
